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Loans and Allowance for Credit Losses - Troubled Debt Restructured Loans and Commitments (Detail) - USD ($) $ in Thousands | Sep. 30, 2020 | Dec. 31, 2019
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Financing Receivable, Troubled Debt Restructurings [Line Items] |  |
Financing Receivable, Troubled Debt Restructuring | $ 11,589 | $ 13,579
Financing Receivable, Troubled Debt Restructuring, Commitment to Lend | 81 | 223
Letter of Credit [Member] |  |
Financing Receivable, Troubled Debt Restructurings [Line Items] |  |
Financing Receivable, Troubled Debt Restructuring, Commitment to Lend | 60 | 60
Unused lines of Credit [Member] |  |
Financing Receivable, Troubled Debt Restructurings [Line Items] |  |
Financing Receivable, Troubled Debt Restructuring, Commitment to Lend | 21 | 163
Accrual Loans [Member] [Member] |  |
Financing Receivable, Troubled Debt Restructurings [Line Items] |  |
Financing Receivable, Troubled Debt Restructuring | 7,078 | 7,542
Non Accrual Loans [Member] |  |
Financing Receivable, Troubled Debt Restructurings [Line Items] |  |
Financing Receivable, Troubled Debt Restructuring | $ 4,511 | $ 6,037

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- Definition Amount of financing receivable modified as troubled debt restructuring. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 40 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=121585226&loc=d3e18845-111554 + Details
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- Definition Amount of unfunded portion of contractual agreement to lend funds to borrower for financing receivable modified as troubled debt restructuring. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 40 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121585226&loc=d3e18794-111554 + Details
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